Inter: Free Variable Typeface for Interface Design
A versatile open-source font family with text and display optical sizes.

Use Inter for navigation, forms and longer interface copy. Its broad weight range helps build hierarchy without introducing another family. Test numerals, punctuation and the actual languages in your product before choosing your final styles.
Download and usage
Download the family from its official site. Distributed under the SIL Open Font License; retain the license when bundling or redistributing font files.
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IBM Plex: Free Sans, Serif and Mono Font Family
A coordinated open-source type system for interface, editorial and code typography.
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